Overview

Wallace Weir is a water control structure on the Knights Landing Ridge Cut where it enters the west side of the Yolo Bypass. Adult salmon have been found in dead-end agricultural ditches upstream of the weir in the Colusa Basin Drain system, especially when flows in the Knights Landing Ridge Cut are high. These fish rarely, if ever, make it back to the Sacramento River to continue their up-stream migration to spawning grounds, thus dying in these dead-end ditches. The earthen dam, which washes away during high flow events, will be replaced with a permanent structure that will prevent migration of salmon and sturgeon into the Colusa Basin Drain. The project also includes a facility to allow for efficient trapping and relocation of fish to the Sacramento River. Completion of this project will help fulfill NMFS BO RPA Action I.7

Next Steps

Construction

Construction started in August 2016. Construction is expected to be completed in 2016.

Planning and Design Status

DWR has been working with Reclamation District (RD) 108 to plan and permit this project. Visit RD 108 Wallace Weir Fish Rescue Facility Page for more information and to download the Initial Study and Mitigated Negative Declaration, which was released in April 2016.